The 70-something woman was living on the street in New York City when Ms. Olson encountered her on her way to a business luncheon. Olson's awareness of the homeless problem in the city already had been heightened by those she had come across previously. She decided to buy Millie a sandwich and orange juice.

The two began to talk and learn more about each other. In the months that followed, Olson began to prepare sandwiches with her two sons to bring to New York City for the homeless population on alternate Sundays.

Fast forward two years, and Olson launched a national organization geared toward taking homeless families off the streets and helping them to achieve self-sufficiency.

Today Olson is founder and president of Family Promise, formerly the National Interfaith Hospitality Network, a volunteer-driven nonprofit organization that works to provide shelter, meals, and support services to homeless families, along with family-mentoring services and job-training programs.

The organization, celebrating its 25th anniversary, now has 182 affiliates in 41 states, with new affiliates joining every year. Its mission, helping those most in need to achieve independence and self-sufficiency, stems from Olson’s personal volunteer work.

“I always had a desire to make a difference in people’s lives,” she says. “I felt strongly that I should involve the religious community – not just churches, but churches, synagogues, and mosques.”

After volunteering on her own to help the homeless in New York City and near her home in Union County, N.J., Olson held a conference that drew 200 guests and helped to raise awareness of the issue.

In the process of meeting regularly to find ways to help those in need, Olson says, the idea was hatched to establish a network of congregations in a variety of faith communities to provide shelter to homeless families. Since running a shelter requires extensive resources, a group of faith communities would share the task, rotating on a weekly basis to provide coverage throughout the year.

The 11 congregations rotated to provide shelter and meals. A van was acquired to transport families to a day program at the local YMCA. Within six weeks, Olson says the families wound up finding affordable housing.

The idea has spread ever since, and now involves more than 6,000 congregations.

Olson says the model of rotating congregations makes the program manageable for small faith communities.

“It allows many congregations to participate, and many volunteers to get involved,” she says. “Families not only feel supported, but many contacts grow out of the involvement.”

And the program has seen results – 77 percent of families served find affordable housing, many in a matter of weeks.

Over the quarter-century history of Family Promise, Olson says, the root of homelessness – poverty – has remained the same.

“Unfortunately, you cannot talk about homelessness without talking about housing,” she says. “Most of the families who come to our program are spending 50 percent or more of their income on rent.”

One medical bill or car repair, she points out, can put a family on the street.

But what has also remained constant is the group of volunteers – currently 160,000 strong – that participate in the organization’s mission through its affiliates.

While it is slightly more challenging now to recruit volunteers – due in large part to declining membership in some congregations – the organization’s congregation-based model makes it relatively easy to find a helping hand.

“I think one of the reasons we have been able to grow is because people really do yearn to make a difference,” she says.

Even after 25 years, her job is still incredibly rewarding. And with more than a half-million beneficiaries of Family Promise – 60 percent of them children – Olson says that tangible differences are being made.

“I know lives are changed,” she says.

And it's not just the lives of those who have regained their independence and found housing. It is also the lives of those who volunteer, the congregants who link faith and social justice together. Every now and then, Olson will hear from a pastor who shares how the spirit of his or her congregation was transformed through the service opportunities.

“The most rewarding part is seeing people caring about people,” Olson says. “You just have to provide a way for people to get involved and make a difference in peoples’ lives.”

Olson sees a very basic lesson in Family Promise: “It shows that we really do care about one another.”